This invention relates to a sealing assembly for a blending apparatus. More particularly, it relates to a sealing arrangement for a vacuum source connected to a blender wherein the blender is rotated and the vacuum source can be connected in a manner such that the risk of contaminants from outside atmosphere or the sealing assembly itself is substantially reduced.
There exists a problem in making connections to a blending apparatus wherein the contents of the blender are held under a vacuum during the mixing operation. In a conventional blender of this type, a vacuum line is usually placed inside a trunion and ultimately interconnected with the inside of the blender. Some means of sealing the inner vacuum line from outside atmosphere must be accomplished as the trunion rotates over the inner vacuum line. In U.S. Pat. No. 3,313,550, a stuffing box is provided for a mixing apparatus and is in the form of a split seal arrangement to be placed around an agitator shaft. The prior art does not provide a solution to the problem of providing a sealing arrangement for a blending apparatus wherein the contents are placed under a vacuum and a sealing assembly is arranged such that the probability of contaminants entering into the blender are reduced to a minimum.
It is an advantage of the present invention to provide a novel sealing assembly for a blending apparatus. Other advantages are a seal arrangement for a blending apparatus wherein a vacuum connection is made and the sealing assembly is provided separately from the blender; a vacuum line is integrally connected to the blending device and is sealed inside of the separate housing through which the vacuum connection to the vacuum source is made; a sealing assembly for a rotating blending apparatus wherein the sealing means for a vacuum connection is made in such a manner that it can be easily disconnected for maintenance purposes; a sealing assembly for a blender with a vacuum connection wherein the sealing assembly can be mounted to a standard blending apparatus with a vacuum connection.